«وَأَمَّا تَخْصِيصُهُ أَيِ الْمُسْنَدِ بِالْإِضَافَةِ أَوِ الْوَصْفِ»
The predicate may be specified by annexation or by a descriptive attribute.
«زَيْدٌ غُلَامُ رَجُلٍ»
Zayd is the servant of a man.
«زَيْدٌ رَجُلٌ عَالِمٌ»
Zayd is a learned man.
In the first case «غلام» is restricted through annexation to a man; in the second, «رجل» is qualified by learning. Both are more determinate assertions than the corresponding unqualified predicate. Neither necessarily means that no one else has the attribute.